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Ritalin: Stimulant for Cancer

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Q. What is Ritalin (Methylphenidate)?

A. Ritalin, manufactured by Ciba-Geigy, is a stimulant and its effects are similar to the effects of other stimulants including amphetamine, methamphetamine, and cocaine.

Q. What does Ritalin treat?

A. Ritalin is used to treat Attention Deficit and Hyperactivity Disorder (ADHD). ADHD is a central nervous system problem of unknown causes that occurs in children of both sexes, but is diagnosed four times more frequently in boys. ADHD is defined by the Merck Manual as "developmentally inappropriate inattention and impulsivity, with or without hyperactivity." Symptoms include distraction, impatience, and difficulty concentrating.

Q. How often is Ritalin prescribed?

A. There are six million prescriptions for Ritalin filled annually. The U.S. pharmacists distribute five times more Ritalin than the rest of the world combined; no other nation prescribes stimulants for its children in such volume. In fact, the United Nations International Narcotics Control Board has on two recent occasions written to U.S. officials expressing concern about the six-fold increase in Ritalin usage since 1990. Approximately 3 to 5 or more percent of U.S. children and teenagers have been or are being prescribed Ritalin.

Q. What are the side effects of Ritalin?

A. As a stimulant of the central nervous system, Ritalin's side effects include increased blood pressure, increased heart rate, increased body temperature, increased alertness and suppressed appetite. Ritalin is typically used on a daily basis with a hiatus on weekends or during the summer. Because it is ingested almost daily for a period of years, there are major concerns over chronic health effects.

Q. Is Ritalin carcinogenic?

A. After more than forty years of prescribing Ritalin, the FDA along with the National Cancer Institute called for more testing "because of its widespread use in human medicine and - lack of data on its potential carcinogenicity." The National Toxicology Program accepted responsibility for conducting trials on carcinogenicity and in June 1993 released results showing that feeding mice Ritalin induced liver tumors including very rare and highly malignant cancers. These results were found at levels close to those routinely prescribed for children. More studies are being planned for testing Ritalin, but the evidence is strong. Animal tests are very good predictors of human health effects. In fact, the International Agency for Research on Cancer suggests that if a chemical is proven to cause cancer in animals, it should be treated as if it were cancer-causing in humans as well.

Q. How did Ciba-Geigy and the FDA respond to information that Ritalin is cancer-causing?

A. The response of the FDA and Ciba-Geigy to the cancer test results were not adequately protective of child health. The FDA deputy drug director said, "We felt physicians and parents should know this and have a right to know this. But it's not enough of a signal that we think kids should be taken off the drug." Ciba-Geigy wrote to 100,000 physicians informing them of the National Toxicology Program's study and reassured them that Ritalin is believed to be "safe and effective" by the FDA.

But with information that Ritalin does cause cancer in laboratory animals, it can not be deemed "safe." Animal tests are very reliable predictors of human effects. Of the 23 known human carcinogens, all were identified as carcinogens in animals first, sometimes decades earlier. It is disconcerting that the FDA is not making a move to ban or limit the use of this drug.

Q. Are there alternatives to Ritalin in the treatment of ADHD?

A. Yes. While Ritalin is the most commonly used drug for attention deficit disorders, now prescribed to 60 to 90 percent of American children with such disorders, there are pharmacological alternatives. There are also non-drug therapies for ADHD and related mental health problems. For example, behavior modification therapy has been particularly effective with ADHD cases.

The treatment recommendations for stimulants like Ritalin almost always recommend concurrent behavioral therapy or psychotherapy. This is particularly important when a child is being treated for ADHD. Diagnosis of ADHD is often made in cases where other problems are prevalent and a comprehensive mental health examination has not been conducted. Poor hearing, learning disabilities, and stress at home may be factors in such misdiagnosis. In one known case, a child was prescribed Ritalin after a five-minute examination and was subsequently taken off of the medication when it was discovered that he was borderline mentally retarded. The causes of childhood impulsivity and hyperactivity must be carefully explored before an ADHD diagnosis is made.

More on Ritalin:
American Academy of Pediatrics… press release

Reading, Writing and Ritalin press release

Samuel S. Epstein, M.D.
Cancer Prevention Coalition
c/o University of Illinois at Chicago
School of Public Health, M/C 922
2121 W. Taylor St.
Chicago, IL 60612


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